Speed Score 2017

Speed Score 2017
Speed Score 2017
Photo: USA Today Sports Images

by Bryan Knowles

Is the 2017 running back class the strongest in recent memory? Scouts seem to think so, projecting multiple first-round picks and plenty of depth on the back end. Only three backs (Todd Gurley, Melvin Gordon, and Ezekiel Elliott) have been taken in the first round since 2012, but 2017 has a chance to match that number.

Devoid of context, the top running backs in the 2017 draft had roughly equivalent days at the NFL Combine. LSU's Leonard Fournette, Florida State's Dalvin Cook, and Stanford's Christian McCaffrey ran within four-hundredths of a second of one another in the 40-yard dash. Speed Score, however, sees a clear winner from this year's running back crop.

Introduced on ESPN Insider back in 2008, Speed Score is Football Outsiders' metric for evaluating running back prospects. It's built on the simple idea that smaller backs tend to run faster than larger backs, so we should be more impressed by a 4.5-second 40-yard dash from a 220-pound back than the same clock reading from a 170-pound back. As such, Speed Score incorporates a back's official time in the 40-yard dash with his weight to produce a measure of his speed given his size using the formula:

(Weight * 200)/(40 time^4).

The average running back who makes it to the NFL will have a Speed Score around 100, with most running back prospects falling between 85 and 110.

Leonard Fournette, however, is not most running backs. Fournette weighed in at 240 pounds, and then went out and ran a 4.51-second 40. That's the fastest time for a back weighing 240-plus pounds since at least 2003, when the NFL's online records begin. It's no surprise, then, that he tops this year's table with a Speed Score of 116.0. While it's not record-setting (Georgia's Keith Marshall set the record with 126.9 last year before being drafted in the seventh round by Washington, then missing the entire season with an elbow injury), it's well above your average first-round pick's score. It also compares very favorably to Ezekiel Elliott (112.7), a comparison Fournette might have to get used to hearing. Couple his great 40 with his game tape and glowing scouting reports (a cross between Bo Jackson and Adrian Peterson, says NFL.com, exploring new depths of hyperbole), and you can see why Fournette is being touted as a top-10 pick come April.

Best Speed Scores, 240-plus pounds, 1999-2017
Year Player School Weight 40 Time Speed Score
2005 Brandon Jacobs Southern Illinois 267 4.56 123.5
2005 Eric Shelton Louisville 246 4.53 116.8
2016 Derrick Henry Alabama 247 4.54 116.3
2017 Leonard Fournette LSU 240 4.51 116.0
2011 Allen Bradford USC 242 4.53 114.9
1999 Ricky Williams Texas 244 4.56 112.9
2005 Nehemiah Broughton Citadel 250 4.59 112.6
2015 Alonzo Harris Louisiana-Lafayette 243 4.56 112.4
2005 Kay-Jay Harris West Virginia 243 4.56 112.4
2000 Jamal Lewis Tennessee 240 4.58 109.1

While no one matched Fournette, most of the highly-touted backs didn't hurt themselves too much in Indianapolis. Both Dalvin Cook (103.3) and Christian McCaffrey (100.3) ended up with top-10 Speed Scores. That's below average for first-round backs, but neither is a disqualifying performance. McCaffrey, in particular, put up strong performances in the vertical jump, lateral agility drills, and receiving tests, while Cook showed off on the bench press. If teams had either player with a first-round grade coming in, they probably saw enough to keep them in the mix after the on-field workouts.

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Now the caveats: Speed Score measures speed in the context of strength and power. Contrary to criticism on Twitter Saturday, Football Outsiders has never said that a larger player with a higher 40 time is actually faster than a smaller player with a lower 40 time because we are not morons. And Speed Score doesn't measure agility, receiving ability, or any of the other aspects related to playing the position. It's still correlated with NFL success, however, and it likes Fournette significantly better than the other touted backs. The 30 pounds he has on either of the other top backs matters when they're running nearly identical times. McCaffrey makes defenders miss. Fournette runs through them. Speed Score is going to like the wrecking ball over the dancer every time, and people just don't run 4.5 40s when they're as large as Fournette is.

This year's other back with a 110-plus Speed Score isn't going to go in the first round. Utah's Joe Williams ran the second-fastest 40 of the day at 4.41 seconds; at 210 pounds, that's a Speed Score of 111.0. Williams' path to the NFL is a very odd one. He was kicked out of UConn for credit card theft and illegal use before going to junior college and putting up strong numbers. He then transferred to Utah, where he actually retired from football during the 2016 season, before coming back when the Utes suffered a plethora of injuries at the position and averaging 156.3 yards per game. To say scouts are concerned about his character and his commitment to football is a massive understatement, but his on-field production and workout numbers may well be worth a late-round flier.

At the bottom of the table, we have some notably bad performances. Technically, the worst Speed Score would have gome to Virginia Tech's Sam Rogers at 78.2, but he's a fullback, and we try not to compare them directly to running backs.

Indiana's Devine Redding is a running back, however, and his Speed Score of 79.9 might bump him from a third-day pick to the undrafted free agent set. His 4.76-second 40 was slower than everyone but Rogers, and none of his other drills particularly impressed. Scouts, Inc. had him as their 24th-ranked running back coming into the combine, and an average of 20.6 running backs have been drafted per year over the last five seasons. Redding needed to stand out from the pack in order to get drafted, and while he arguably achieved that goal, it wasn't exactly in the manner one would have hoped.

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Speed Score doesn't raise any huge red flags for any highly-regarded prospects. Toledo's Kareem Hunt only ran a 4.62-second 40 when he was aiming for a sub-4.5, finishing with a 94.8 Speed Score. Corey Clement (91.7) and Donnel Pumphrey (87.4) are also likely unhappy with their combine performances; both are pegged as third-day picks who might see their stocks fall after running slower than 4.6.

Among the top backs, Tennessee's Alvin Kamara put up the worst numbers, but even they weren't actually bad. He finishes with a Speed Score of 99.0 after running a 4.56-second 40, but that will likely be offset by the fact that he reportedly "crushed" the interview section -- Bucky Brooks called him the biggest combine winner in this year's running back class. Speed Score wasn't overly impressed, but it's not exactly dropping Kamara into the bust category or anything like that.

Looking at the overall class, there are plenty of solid mid-round backs available. Jeremy McNichols, Marlon Mack, Brian Hill, and Elijah McGuire all had Speed Scores over 100 and are considered mid-round picks. With a deep class, it becomes harder to justify taking a running back early, and history backs that up -- only one of the top ten leaders in rushing yards this season went in the first round. You know someone's going to be chasing the next Ezekiel Elliott, though, and Speed Score has a clear favorite. If your team goes all-in on a running back this year, hope it's Leonard Fournette.

2017 Speed Scores
Player School Weight 40 Time Speed Score
Leonard Fournette LSU 240 4.51 116.0
Joe Williams Utah 210 4.41 111.0
T.J. Logan North Carolina 196 4.37 107.5
Jeremy McNichols Boise State 214 4.49 105.3
Marlon Mack South Florida 213 4.5 103.9
Dalvin Cook Florida State 210 4.49 103.3
De'Angelo Henderson Coastal Carolina 208 4.48 103.3
Brian Hill Wyoming 219 4.54 103.1
Elijah McGuire Louisiana-Lafayette 214 4.53 101.6
Christian McCaffrey Stanford 202 4.48 100.3
James Conner Pittsburgh 233 4.65 99.7
Samaje Perine Oklahoma 233 4.65 99.7
Christopher Carson Oklahoma State 218 4.58 99.1
Alvin Kamara Tennessee 214 4.56 99.0
Aaron Jones Texas-El Paso 208 4.56 96.2
Wayne Gallman Clemson 215 4.6 96.0
Jamaal Williams BYU 212 4.59 95.5
Kareem Hunt Toledo 216 4.62 94.8
Tarik Cohen North Carolina A&T 179 4.42 93.8
Stanley Williams Kentucky 190 4.51 91.8
Corey Clement Wisconsin 220 4.68 91.7
Dare Ogunbowale Wisconsin 213 4.65 91.1
Rushel Shell West Virginia 227 4.74 89.9
Donnel Pumphrey San Diego State 176 4.48 87.4
Jahad Thomas Temple 190 4.63 82.7
Devine Redding Indiana 205 4.76 79.9

Did not run: Justin Davis, Matt Dayes, D'Onta Foreman, Elijah Hood, De'Veon Smith


21 comments, Last at 03 Apr 2019, 7:31pm

#1 by Bryan Knowles // Mar 05, 2017 - 1:33pm

The obligatory notes here: no stat stands on it's own devoid of context; otherwise, we'd be talking about how Joe Williams should be a first-round pick and so forth. One could make an argument that McCaffrey had the most impressive day at the combine overall when you take everything into account -- it just so happens that the areas he's strongest in are the areas Speed Score doesn't measure. So the fact that he's slightly above-average in this metric ~and~ is arguably the best receiver in the class in the passing game is impressive.

Kamara's SPARQ score, measuring overall athleticism, was the highest at the combine as well, so again, not the only measurement out there.

But good lord, Fournette's 40-yard time is impressive. I ~hate~ drafting running backs in the first round and I think Fournette should go top-ten. He'll probably drop a few pounds before the season -- I remember reading his goal was 235 -- and you'd assume that would subtract a few fractions from his speed.

He'll do best in a scheme were he can build up a head of steam behind the line of scrimmage -- lots of shotgun and I-formation stuff where he can alter his path 3-5 yards behind the line rather than a McCaffery-esque quick cut. Let him do that, and he's just going to juggernaught over people.

Matt Waldman had a good piece on his strengths and weaknesses here:

Points: 0

#21 by fb29 // Apr 03, 2019 - 7:31pm

Having followed speed score for maybe ten years now? I forget how long it's been, but it seems to be useless.

The only correlation I can see is that too high a speed score means the player won't stay healthy. Bones and ligaments can only handle so much fast twitch muscle.

Any thoughts on finding a new metric? Something like Playmaker Score for Running Backs?

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#2 by Bryan Knowles // Mar 05, 2017 - 1:37pm

Also, cut in the editing process: Sam Rogers, the fullback with the lowest theoretical speed score, ran a 4.93. That's not just the slowest time this year, that's the slowest I found for a "running back" (or fullback) going back to at least 1999, and was slower than a couple offensive linemen.

Fullbacks aren't running backs, and speed score really isn't relevant for them, but I do enjoy 40s that could be timed with an hourglass.

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#3 by Purds // Mar 05, 2017 - 4:50pm

Thanks for the work. I watched some of the combine, and I am a Colts fan, but I don't want them to take a RB in the first round. That said, McCaffrey on the right team will be a terror. He looked incredibly comfortable in the lateral drills and in the receiving drills. Not comfortable, really, but incredibly proficient. Very confident, with abilities to match. Can you imagine him on the right team, like the Patriots, where RBs as receivers or scamper backs are utilized extremely well, even if they're only okay athletes? He'd be a game changer. Of course, if they just put him back in an I-formation and run him into the line, we won't see anything special. But, in the right system, he's going to be amazing.

I didn't see Fournette in his other drills. He seems like a guy who can succeed in almost any system, though.

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#4 by T-Vector // Mar 05, 2017 - 6:08pm

I think the fears I have about Fournette is that he and Henry are so similar. Henry is on the perfect team/scheme for his talents. Is he worth a first round pick? He wasn't even able to win the first string job.

I suspect the "head of steam" RB is becoming a liability in modern offenses.

This metric seems outdated in today's game.

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#5 by Bryan Knowles // Mar 05, 2017 - 7:31pm

You'd be surprised. Here are the speed scores of the ten backs with the most rushing yards in 2016:

Ezekiel Elliot: 112.7
Jordan Howard: N/A (did not run 40)
DeMarco Murray: 116.8
Jay Ajayi: 101.3
Le'Veon Bell: 102.7
LeSean McCoy: 96.6
David Johnson: 109.3
LeGarrette Blount: 98.8
Devonta Freeman: 93.6
Lamar Miller: 119.5

So, certainly not the end-all be-all, but you're not seeing a lot of low-90s or upper-80s among the most productive backs in the NFL.

The results are also still correlated with DYAR and rushing yards. Is it a crystal ball stat? No, of course not -- but it's very useful.

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#6 by Dan // Mar 06, 2017 - 5:04am

It's pretty astounding how bad Fournette's vertical was, given that he's on top of this speed score ranking. Going by PFR's database, since 2000 Fournette is only the 7th RB with a vertical of 28.5" or worse (joining Kalvin McRae, Justin Forsett, Kenny Hilliard, Mike Hart, Kregg Lumpkin, and Alex Collins).

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#9 by Bryan Knowles // Mar 06, 2017 - 1:23pm

Yeah, that was a fun...I want to say half hour, when everyone was panicking over Fournette's vertical.

Harvard just came out with a piece trying to correlate the various drills to success, and the vertical jump was ~somewhat~ relevant for running backs-- less than the 40, the 3-cone, and weight, but more than, say, the shuttle or the bench press. Fournette was good enough everywhere else that I'd shrug off the vertical jump, but it shows he's not a -perfect- prospect.

I'll link the article here, it's got great graphs with error bars and everything.


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#10 by T-Vector // Mar 06, 2017 - 5:43pm

This is a pretty incredible study. The forty, derided by almost any ex-player, is one of the most important drills to show future success?

I think I have to look at the study more closely.

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#7 by johonny // Mar 06, 2017 - 10:06am

Velocity * mass = momentum. A larger mass at the same speed has more momentum. Perhaps you should call it a momentum score :)

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#8 by Bryan Knowles // Mar 06, 2017 - 1:15pm

Were I creating it today, I'd give it a silly acronym instead, 'cause that's the kind of thing I do -- you know, like ALEX. It's Bill Barnwell's stat though, and he gave it a "regular" name. Ah well! We shall persevere.

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#11 by Tomlin_Is_Infallible // Mar 06, 2017 - 6:37pm

look who didn't read the formula/equation

The standard is the standard!

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#12 by Eddo // Mar 07, 2017 - 11:54am

Right, mometum = mass * velocity.
Kinetic energy = 0.5 * mass * velocity^2.

This is velocity^4, though. It's third-order kinetic energy, more or less.

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#14 by Tomlin_Is_Infallible // Mar 07, 2017 - 2:22pm

and the fact it's divided by....
The standard is the standard!

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#16 by Eddo // Mar 08, 2017 - 11:41am

I'm not following. Speed score is divided by time, just like velocity is.

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#17 by Tomlin_Is_Infallible // Mar 08, 2017 - 5:15pm

speedscore = pounds per second per second per second per second

my point is it doesn't relate in a direct way to momentum or kinetic energy.

The standard is the standard!

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#18 by Eddo // Mar 08, 2017 - 5:22pm

Ah, yeah, OK. It's not directly related, no - if you hold mass constant, it's proportional to KE^2 (or momentum^4).

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#19 by Dan // Mar 14, 2017 - 3:52am

Speed score is basically just a linear equation. Every 20 pounds is worth about 0.10 of 40 time, which is worth 10 points of speed score. Average is set at 215 lbs., 4.55 40, which is a speed score of 100.

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#20 by Tomlin_Is_Infallible // Mar 15, 2017 - 4:24pm

uhhhhhhhhhhhhhhhhhhh no


The standard is the standard!

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#13 by WiFiGuy // Mar 07, 2017 - 12:27pm

Does this Speed Score report supersede FO's BackCast score which was introduced last year?

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#15 by Aaron Schatz // Mar 07, 2017 - 4:57pm

No, the opposite. BackCast is the next step after Speed Score and Nathan Forster is working on it now.

Points: 0

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